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“The court will not rely on extrapolated numbers from tiny samples sizes and otherwise flawed data.”


<div align=right>-- Judge Julie A. Robinson, quoted in: [https://www.nytimes.com/2018/06/19/opinion/a-crusader-against-voter-fraud-fails-to-prove-his-case.html A crusader against voter fraud fails to prove his case], ''New York Times'', 19 June 2018 </div>
"Using scientific language and measurement doesn’t prevent a researcher from conducting flawed experiments and drawing wrong conclusions — especially when they confirm preconceptions."


==Redefining statistical significance==
<div align=right>-- Blaise Agüera y Arcas, Margaret Mitchell and Alexander Todoorov, quoted in: The racist history behind facial recognition, ''New York Times'', 10 July 2019</div>
[https://news.uchicago.edu/article/2017/09/01/scholars-take-aim-false-positives-research Scholars take aim at false positives in research]<br>
by Thomas Gaulkin, ''UChicagoNews'', 1 September 2017
 
University Chicago economist John List is one of 72 collaborators whose commentary,
[https://www.nature.com/articles/s41562-017-0189-z.epdf?author_access_token=Eb6x88zTNQ7PuVxPt1CpXdRgN0jAjWel9jnR3ZoTv0PlqY8PQKtlL9OP0czNSVZ5rodrqWv-lxLd4whdDH-qvHpF5PQtT1U4AblMVaKnbDH0ctY2yThyrB_ccetKNmK4sasDTgzcxT5_u2wTJ8C6sg%3D%3D Redfine statistical significance], was just published in ''Nature Human Behavior''.  The subtitle reads,  
"We propose to change the default P-value threshold for statistical significance from 0.05 to 0.005 for claims of
new discoveries."
 
[http://rsos.royalsocietypublishing.org/content/3/9/160384 The natural selection of bad science]
 
[http://www.sciencemag.org/news/2017/07/it-will-be-much-harder-call-new-findings-significant-if-team-gets-its-way It will be much harder to call new findings ‘significant’ if this team gets its way]


==In progress==
==In progress==
[https://medium.com/pew-research-center-decoded Decoded]
[https://www.nytimes.com/2018/11/07/magazine/placebo-effect-medicine.html What if the Placebo Effect Isn’t a Trick?]<br>
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by Gary Greenberg, ''New York Times Magazine'', 7 November 2018
[That Huge Mediterranean Diet Study Was Flawed. But Was It Wrong?]<br>
by Gina Kolata, ''New York Times'', 13 June 2018
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[https://www.nytimes.com/2018/06/02/us/puerto-rico-death-tolls.html Why are the death tolls in Puerto Rico from Hurricane Maria so different?]<br>
by Sheri Fink, ''New York Times'', 2 June 2018
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[https://www.theonion.com/leading-probability-researchers-confounded-by-three-cow-1822174747]


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[https://www.nytimes.com/2019/07/17/opinion/pretrial-ai.html The Problems With Risk Assessment Tools]<br>
[https://www.nytimes.com/2018/03/29/opinion/2016-exit-polls-election.html The 2016 exit polls led us to misinterpret the 2016 election]<br>
by Chelsea Barabas, Karthik Dinakar and Colin Doyle, ''New York Times'', 17 July 2019
by Thomas Edsall, ''New York Times'', 29 March 2018


==Hurricane Maria deaths==
Laura Kapitula sent the following to the Isolated Statisticians e-mail list:


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:[Why counting casualties after a hurricane is so hard]<br>
[http://www.rss.org.uk/RSS/Get_involved/Statistic_of_the_year/RSS/Get_involved/Statistic_of_the_Year_.aspx 2017 Statistic of the year]<br>
:by Jo Craven McGinty, Wall Street Journal, 7 September 2018
from the Royal Statistical Society


[http://probabilityandlaw.blogspot.com/2018/01/on-lawnmowers-and-terrorists-again.html]
The article is subtitled: Indirect deaths—such as those caused by gaps in medication—can occur months after a storm, complicating tallies
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Laura noted that
:[https://www.washingtonpost.com/news/fact-checker/wp/2018/06/02/did-4645-people-die-in-hurricane-maria-nope/?utm_term=.0a5e6e48bf11 Did 4,645 people die in Hurricane Maria? Nope.]<br>
:by Glenn Kessler, ''Washington Post'', 1 June 2018


[https://www.nytimes.com/2018/02/02/opinion/sunday/football-two-point-conversion.html Force overtime? Or go for the win?]<br>
The source of the 4645 figure is a [https://www.nejm.org/doi/full/10.1056/NEJMsa1803972 NEJM article]. Point estimate, the 95% confidence interval ran from 793 to 8498.
by Jesse Walker, Jane L. Risen, Thomas Gilovich and Richard Thaler , New York Times, 27 February 2018
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[https://www.nytimes.com/2018/01/15/us/politics/gerrymandering-math.html A case for math, not ‘gobbledygook,’ in judging partisan voting maps]<br>
by Adam Liptak, ''New York Times'', 15 January 2018


[https://www.propublica.org/article/supreme-court-errors-are-not-hard-to-find It’s a fact: Supreme Court errors aren’t hard to find] (ProPublica, 17 Oct 2017)
President Trump has asserted that the actual number is
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[https://twitter.com/realDonaldTrump/status/1040217897703026689 6 to 18].
https://www.nytimes.com/2018/01/17/us/politics/factcheck-trump-black-americans-support.html Trump Falsely Claims His Approval Among Black Americans Has Doubled]<br>
The ''Post'' article notes that Puerto Rican official had asked researchers at George Washington University to do an estimate of the death toll. That work is not complete.
by Linda Qiu, ''New York Times'', 17 January 2018
[https://prstudy.publichealth.gwu.edu/ George Washington University study]
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[https://www.nytimes.com/2017/11/07/world/americas/mass-shootings-us-international.html What explains U.S. mass shootings? International comparisons suggest an answer]<br>
by Max Fisher and Josh Keller , ''New York Times'', 7 November 2017
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[https://www.theguardian.com/us-news/2017/sep/22/college-free-speech-violence-survey-junk-science 'Junk science': experts cast doubt on widely cited college free speech survey]<br>
by Lois Beckett, The Guardian, 22 September 2017


[https://www.washingtonpost.com/opinions/a-chilling-study-shows-how-hostile-college-students-are-toward-free-speech/2017/09/18/cbb1a234-9ca8-11e7-9083-fbfddf6804c2_story.html A chilling study shows how hostile college students are toward free speech]<br>
:[https://fivethirtyeight.com/features/we-still-dont-know-how-many-people-died-because-of-katrina/?ex_cid=538twitter We sttill don’t know how many people died because of Katrina]<br>
''Washington Post''
:by Carl Bialik, FiveThirtyEight, 26 August 2015
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[https://www.nytimes.com/2017/10/03/us/politics/las-vegas-shooting-gun-claims-fact-check.html Spurious chart, data on N.R.A. spending mislead in gun debate]<br>
by Linda Qiu, ''New York Times'', 3 October 2017
 
http://www.aei.org/publication/chart-of-the-day-more-guns-less-gun-violence-between-1993-and-2013/
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[https://www.vox.com/science-and-health/2017/8/28/16211392/100-500-year-flood-meaning The “500-year” flood, explained: why Houston was so underprepared for Hurricane Harvey]<br>
by Dara Lind, ''Vox'', 28 August 2017
 
The subtitle notes that Hurricane Harvey has produced Houston's  third “500-year” flood in the past three years.
 
[https://www.wsj.com/articles/harveys-test-businesses-struggle-with-flawed-insurance-as-floods-multiply-1504022632 Harvey’s test: Businesses struggle with flawed insurance as floods multiply]<br>
by Ruth Simon and Cameron McWhirter, ''Wall Street Journal'', 29 August 2017
 
"Twenty storms causing a billion dollars or more in damage have taken place since 2010, not including Hurricane Harvey, compared with nine billion-dollar floods in the full decade of the 1980s, according to inflation-adjusted estimates from the National Oceanic and Atmospheric Administration."
 
Brigitte Baldi StatEd [https://fivethirtyeight.com/features/its-time-to-ditch-the-concept-of-100-year-floods/ It’s time To ditch the concept of ‘100-year floods’]


[http://floodsafety.com/national/property/risk/]
[https://pubs.usgs.gov/fs/FS-229-96/ USGS Fact Sheet]
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[https://www.sciencealert.com/watch-here-s-the-best-guide-we-ve-seen-to-how-correlation-and-causation-work Here's Why Sometimes Correlation Does Actually Imply Causation]
[https://www.nytimes.com/2018/09/11/climate/hurricane-evacuation-path-forecasts.html These 3 Hurricane Misconceptions Can Be Dangerous. Scientists Want to Clear Them Up.]<br>
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[https://journals.ametsoc.org/doi/abs/10.1175/BAMS-88-5-651 Misinterpretations of the “Cone of Uncertainty” in Florida during the 2004 Hurricane Season]<br>
[https://www.nytimes.com/2017/08/29/magazine/the-new-front-in-the-gerrymandering-wars-democracy-vs-math.html?_r=0 The new front in the gerrymandering wars: Democracy vs. math]
[https://www.nhc.noaa.gov/aboutcone.shtml Definition of the NHC Track Forecast Cone]
 
[https://arxiv.org/pdf/1709.01596.pdf Evaluating Partisan Gerrymandering in Wisconsin]
 
[https://www.nytimes.com/2017/10/06/opinion/sunday/computers-gerrymandering-wisconsin.html How computers turned gerrymandering into a science]<br>
by Jordan Ellenberg, ''Sunday Review'', ''New York Times'', 6 October 2017
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[https://www.popsci.com/moderate-drinking-benefits-risks Remember when a glass of wine a day was good for you? Here's why that changed.]
[https://www.nytimes.com/2017/08/22/opinion/exxon-climate-change-.html What Exxon Mobil didn’t say about climate change]<br>
''Popular Science'', 10 September 2018
by Geoffrey Supran and Naomi Oreskes, ''New York Times'', 22 August 2017
 
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[https://www.reuters.com/article/us-facebook-advertising-research/facebook-digital-ads-figures-differ-from-census-data-analyst-idUSKCN1BH0H3 Facebook digital ads figures differ from census data: analyst]
[https://www.economist.com/united-states/2018/08/30/googling-the-news Googling the news]<br>
''Economist'', 1 September 2018


[https://www.cnbc.com/2018/09/17/google-tests-changes-to-its-search-algorithm-how-search-works.html We sat in on an internal Google meeting where they talked about changing the search algorithm — here's what we learned]
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[https://qz.com/1059862/dont-base-your-amazon-purchases-on-the-number-of-reviews-a-product-has/ Don’t base all your Amazon purchases on the number of reviews a product has]<br>
[http://www.wyso.org/post/stats-stories-reading-writing-and-risk-literacy Reading , Writing and Risk Literacy]
by Corinne Purtill, Quartz, 23 August 2017


[http://journals.sagepub.com/doi/full/10.1177/0956797617711291 The Love of Large Numbers: A Popularity Bias in Consumer Choice]
[http://www.riskliteracy.org/]
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[https://twitter.com/i/moments/1025000711539572737?cn=ZmxleGlibGVfcmVjc18y&refsrc=email Today is the deadliest day of the year for car wrecks in the U.S.]


==Some math doodles==
==Some math doodles==

Latest revision as of 20:58, 17 July 2019


Forsooth

Quotations

“We know that people tend to overestimate the frequency of well-publicized, spectacular events compared with more commonplace ones; this is a well-understood phenomenon in the literature of risk assessment and leads to the truism that when statistics plays folklore, folklore always wins in a rout.”

-- Donald Kennedy (former president of Stanford University), Academic Duty, Harvard University Press, 1997, p.17

"Using scientific language and measurement doesn’t prevent a researcher from conducting flawed experiments and drawing wrong conclusions — especially when they confirm preconceptions."

-- Blaise Agüera y Arcas, Margaret Mitchell and Alexander Todoorov, quoted in: The racist history behind facial recognition, New York Times, 10 July 2019

In progress

What if the Placebo Effect Isn’t a Trick?
by Gary Greenberg, New York Times Magazine, 7 November 2018

The Problems With Risk Assessment Tools
by Chelsea Barabas, Karthik Dinakar and Colin Doyle, New York Times, 17 July 2019

Hurricane Maria deaths

Laura Kapitula sent the following to the Isolated Statisticians e-mail list:

[Why counting casualties after a hurricane is so hard]
by Jo Craven McGinty, Wall Street Journal, 7 September 2018

The article is subtitled: Indirect deaths—such as those caused by gaps in medication—can occur months after a storm, complicating tallies

Laura noted that

Did 4,645 people die in Hurricane Maria? Nope.
by Glenn Kessler, Washington Post, 1 June 2018

The source of the 4645 figure is a NEJM article. Point estimate, the 95% confidence interval ran from 793 to 8498.

President Trump has asserted that the actual number is 6 to 18. The Post article notes that Puerto Rican official had asked researchers at George Washington University to do an estimate of the death toll. That work is not complete. George Washington University study

We sttill don’t know how many people died because of Katrina
by Carl Bialik, FiveThirtyEight, 26 August 2015

These 3 Hurricane Misconceptions Can Be Dangerous. Scientists Want to Clear Them Up.
Misinterpretations of the “Cone of Uncertainty” in Florida during the 2004 Hurricane Season
Definition of the NHC Track Forecast Cone


Remember when a glass of wine a day was good for you? Here's why that changed. Popular Science, 10 September 2018


Googling the news
Economist, 1 September 2018

We sat in on an internal Google meeting where they talked about changing the search algorithm — here's what we learned


Reading , Writing and Risk Literacy

[1]


Today is the deadliest day of the year for car wrecks in the U.S.

Some math doodles

<math>P \left({A_1 \cup A_2}\right) = P\left({A_1}\right) + P\left({A_2}\right) -P \left({A_1 \cap A_2}\right)</math>

<math>P(E) = {n \choose k} p^k (1-p)^{ n-k}</math>

<math>\hat{p}(H|H)</math>

<math>\hat{p}(H|HH)</math>

Accidental insights

My collective understanding of Power Laws would fit beneath the shallow end of the long tail. Curiosity, however, easily fills the fat end. I long have been intrigued by the concept and the surprisingly common appearance of power laws in varied natural, social and organizational dynamics. But, am I just seeing a statistical novelty or is there meaning and utility in Power Law relationships? Here’s a case in point.

While carrying a pair of 10 lb. hand weights one, by chance, slipped from my grasp and fell onto a piece of ceramic tile I had left on the carpeted floor. The fractured tile was inconsequential, meant for the trash.

BrokenTile.jpg

As I stared, slightly annoyed, at the mess, a favorite maxim of the Greek philosopher, Epictetus, came to mind: “On the occasion of every accident that befalls you, turn to yourself and ask what power you have to put it to use.” Could this array of large and small polygons form a Power Law? With curiosity piqued, I collected all the fragments and measured the area of each piece.

Piece Sq. Inches % of Total
1 43.25 31.9%
2 35.25 26.0%
3 23.25 17.2%
4 14.10 10.4%
5 7.10 5.2%
6 4.70 3.5%
7 3.60 2.7%
8 3.03 2.2%
9 0.66 0.5%
10 0.61 0.5%
Montante plot1.png

The data and plot look like a Power Law distribution. The first plot is an exponential fit of percent total area. The second plot is same data on a log normal format. Clue: Ok, data fits a straight line. I found myself again in the shallow end of the knowledge curve. Does the data reflect a Power Law or something else, and if it does what does it reflect? What insights can I gain from this accident? Favorite maxims of Epictetus and Pasteur echoed in my head: “On the occasion of every accident that befalls you, remember to turn to yourself and inquire what power you have to turn it to use” and “Chance favors only the prepared mind.”

Montante plot2.png

My “prepared” mind searched for answers, leading me down varied learning paths. Tapping the power of networks, I dropped a note to Chance News editor Bill Peterson. His quick web search surfaced a story from Nature News on research by Hans Herrmann, et. al. Shattered eggs reveal secrets of explosions. As described there, researchers have found power-law relationships for the fragments produced by shattering a pane of glass or breaking a solid object, such as a stone. Seems there is a science underpinning how things break and explode; potentially useful in Forensic reconstructions. Bill also provided a link to a vignette from CRAN describing a maximum likelihood procedure for fitting a Power Law relationship. I am now learning my way through that.

Submitted by William Montante